In application Ser. No. 602,876, now abandoned for "Crystalline Alumina Orthodontic Bracket", filed on the same day as this application and assigned to the same assignee as this application, there is disclosed orthodontic brackets comprising as a load bearing member crystalline alumina. As is disclosed in said application, one of the problems inherent in the use of crystalline alumina orthodontic brackets is bonding them to teeth (or to any other substrate) because of the high surface energy of crystalline alumina.
This invention relates to one means for enhancing the bond of crystalline alumina to substrates. While the invention is described chiefly in terms of its use in connection with orthodontic brackets, the invention is applicable to the bonding of crystalline alumina articles to any substrate.